Laterally diffused MOSFET (LDMOS) devices are asymmetric power MOSFETs (metal-oxide-semiconductor field-effect transistors) designed for low on-resistance and high blocking voltage. LDMOS devices are commonly used as switching power FETs in power converter integrated circuits, among other applications.
The specific resistance Rsp, the gate charge Qg, the Rsp*Qg product figure of merit (FOM), the source-drain breakdown voltage BVdss, and the safe operating area (SOA) are important device parameters, operation characteristics, or design considerations, among others, that affect the performance, efficiency, and reliability characteristics of LDMOS devices. A lower Rsp*Qg product FOM, for example, generally results in better power conversion efficiency in power converter applications, typically for higher switching frequency applications. Therefore, evolving design requirements for greater power conversion, lower power loss, and/or greater performance efficiency in power converter applications, for example, have led to improvements in LDMOS device design and performance. However, there are various tradeoffs between the device parameters. Such tradeoffs generally limit the ability to simply select, choose, adjust, or tune these parameters for any given design.